The prior art soybean serves to make soybean milk. Only one filtering operation is performed and then the soybean is ground and then the soybean dregs are deserted. However the dregs still have 30% nutrition. Thus to desert the soybean dregs will make the cost for making milk being too high. If the dregs are reused manually, it will cause that the soybean milk is to light to be acceptable by users. Furthermore, more labor is needed. Thus the prior art is not economic.
To achieve above object, the present invention provides a complex high-density soybean grinder which reuse soybean dregs automatically, while the density of the soybean is still high.